Answer:
Longer than 27.7 minutes.
Step-by-step explanation:
When the distribution is normal, we use the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question, we have that:

The slowest quarter of customers will require longer than how many minutes (to the nearest tenth) for a simple haircut?
Longer than the 100 - 25 = 75th percentile of times, which is X when Z has a pvalue of 0.75. So X when Z = 0.675. So




So
Longer than 27.7 minutes.
Uh mhmm where is the choice?
Answer:
y = 2x
the formula for linear equations are y = mx+c,
where m is the gradient,
and c is the y-intercept
to find m (the gradient):
1. pick to points on the graph (eg. -2,-4 and 2,4)
2 substitute the values into the formula for gradient y2-y1/x2-x1.
m = y2-y1/x1-x2
= -4 -4/-2-2
= -8/-4
= 2
to find c (y-intercept):
- the y-intercept is where the graph cuts the y axis
- in this graph, the y-intercept is 0
hence,
c = 0
substitute m = 2 and c = 0 to y = mx+c,
y = 2x + 0
y = 2x
hence, the equation that best represents the relationship shown in the graph is y = 2x.